Prehospital Tourniquet Usage and Diabetes Mellitus Associated with Increased Incidence, Odds, and Risk of Acute Kidney Injury: A Pilot Study.

INTRODUCTION: Tourniquets are the standard of care for civilian and military prehospital treatment of massive extremity hemorrhages. Over the past 17 years, multiple military studies have demonstrated rare complications related to tourniquet usage. These studies may not translate well to civilian populations due to differences in baseline health. Experimental studies have demonstrated increased rates of post-traumatic acute kidney injuries (AKIs) in rats with obesity and increased oxidative stress, suggesting that comorbidities may affect AKI incidence with tourniquet usage. Two recently published retrospective studies, focused on the safety of tourniquets deployed within civilian sectors, documented increased incidence of AKI in patients with a prehospital tourniquet as compared to previously published military results. This study aimed to provide descriptive data concerning the association between the use of prehospital tourniquets and AKIs amongst civilian patient populations as AKIs increase mortality in hospitalized patients. METHODS: This was a single-center, observational, cross-sectional, pilot study involving chart review of participants presenting to a tertiary Level 1 trauma center. Patient data were extracted from prehospital and hospital electronic medical records. For this study, AKI was defined using the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. RESULTS: A total of 255 participants were included. Participants with a history of diabetes mellitus had a significantly higher incidence of AKI as compared to those without. Analysis revealed an increased odds of AKI with diabetes in association to the use of a prehospital tourniquet. Participants with diabetes had an increased relative risk of AKI in association to the use of a prehospital tourniquet. The incidence of AKI was statistically higher than what was previous reported in the military population in association with the use of a prehospital tourniquet. CONCLUSION: The incidence of AKIs was higher than previously reported. Patients with diabetes had an associated higher risk and incidence of sustaining an AKI after the use of a prehospital tourniquet in association with the use of a prehospital tourniquet. This may be due to the known deleterious effects of diabetes mellitus on renal function. This study provides clinically relevant data that warrant further multi-site investigations to further investigate this study's associated findings and potential causation. It also stresses the need to assess whether renally-impacting environmental and nutritional stressors affect AKI rates amongst military personnel and others in which prehospital tourniquets are used.

Distal femur versus humeral or tibial IO, access in adult out of hospital cardiac resuscitation.

BACKGROUND: Intraosseous (IO) vascular access is a well-established method for fluid and drug administration in the critically ill. The Food and Drug Administration has approved adult IO access at the proximal humerus, proximal tibia, and the sternum; all three sites have significant limitations. The Distal Femur is away from the chest, with high flow rates. The objective of this study was to evaluate the distal femur site during resuscitation of adult out-of-hospital cardiac arrest. METHODS: A retrospective analysis of adult out of hospital cardiac arrest patients treated by the San Antonio Fire Department. IO access was obtained by first-responders (paramedics or EMT-basic) or EMS paramedics. All resuscitation attempts from 2017 to 2018 data were analyzed. The protocol did not dictate the preference of IO site. The primary measure: number of OHCA patients in each subgroup: IO femur, IO humerus, IO tibia. Secondary measures: paramedic or basic operator, dislodgement rate, and total fluid infused. RESULTS: There were 2,198 patients meeting inclusion criteria: 888 femur, 696 humerus, 432 tibia. Distal femur increased 2.5 times in the 2018 cohort compared to the 2017 cohort, with a corresponding decrease in humerus (factor of 0.29). Proximal tibia remained unchanged. Dislodgement rates and total infusion (ml) remained unchanged. CONCLUSIONS: The distal femur IO was feasible and associated with similar measured performance parameters as other IO sites in adult OHCA for both advanced and basic life support personnel.

Stewardship of Prehospital Low Titer O-Positive Whole Blood in a Large Urban Fire-Based EMS System.

Introduction: Trauma is the leading cause of death for those aged 1 to 46 years with most fatalities resulting from hemorrhage prior to arrival to hospital. Hemorrhagic shock patients receiving transfusion with 15 minutes experience lower mortality. Prehospital blood transfusion has many legal, fiduciary, and logistical issues. The San Antonio Fire Department participates in a consortium designed to enhance the stewardship of prehospital whole blood. This study aimed to stratify blood usage amongst the field supervisors and special operations units that carry whole blood. Methods: This was a 12-month retrospective analysis of blood usage. Blood tracking forms (used for either blood exchange of transfusion) were cross referenced with city financial records to determine blood usage patterns in the 7th Largest City in the US. We used descriptive statistics, compared usage ratios, and chi-square to compare dichotomized data. Results: A total of 363 whole blood units were obtained and 248 (68.3%) units of whole blood were transfused. EMS field supervisors transfused 74% of whole blood vs. 44% for special operations ambulances (p= <0.001). Response vehicles located in densely populated areas had the highest usage rates. All blood units were either transfused or returned for a zero blood unit wastage for expiration. Conclusion: The information contained within this work can provide other EMS agencies with a basic framework for comparison. The data from the SAFD's whole blood transfusion rate coupled with the clinical transfusion guideline has provided some insight for prospective agencies considering adopting a whole blood program. EMS systems and municipalities with similar characteristics can project their own whole blood needs and make informed decisions regarding program feasibility and design.

Adverse events following emergent prehospital sedation of patients with behavioral emergencies: A retrospective cohort study.

Background: Patients presenting to emergency medical services (EMS) with behavioral emergencies may require emergent sedation to facilitate care, but concerns about sedation-related adverse events (AEs) exist. This study aimed to describe the frequency of AEs following emergent prehospital sedation with three types of sedative agents: ketamine, benzodiazepines and antipsychotics. Methods: This retrospective cohort study included patients ≥ 15 years who presented to 1031U.S. EMS agencies in calendar year 2019 with behavioral emergencies necessitating emergent prehospital sedation. Serious AEs (SAE) included cardiac arrest, invasive airway placement, and severe oxygen desaturation (<75%). Less-serious AEs included positive pressure ventilation, any oxygen desaturation (<90%), oropharyngeal or nasopharyngeal airway placement, and suctioning. The need for additional sedation was also assessed. Findings: Of 7973 patients, 1996 received ketamine; 4137 received a benzodiazepine; 1532 received an antipsychotic agent; and 308 received an indeterminant agent. Cardiac arrest occurred in 11 patients (0·1%) and any SAE occurred in 165 patients (2·1%). Invasive airway placement was more frequent with ketamine (40, 2·0%) compared with benzodiazepines (17, 0·4%) or antipsychotics (3, 0·2%). Oxygen desaturation below 75% also occurred more frequently with ketamine (51, 2·6%) than with benzodiazepines (52, 1·3%) or antipsychotics (14, 0·9%). Patients sedated with ketamine were less likely to require additional sedation. Propensity-matching to minimize potential confounding between patient condition, sedative choice and AEs did not meaningfully alter the results. Interpretation: Although SAEs were rare among patients receiving emergent prehospital sedation, prehospital clinicians should remain mindful of the potential risks and monitor patients closely. Funding: None.

More sophisticated than a drink cooler or an old sphygmomanometer but still not adequate for prehospital blood: A market review of commercially available equipment for prehospital blood transport and administration.

BACKGROUND: Hemorrhage is the leading cause of death in trauma patients with most fatalities occurring before reaching a higher level of care-this applies to both the civilian setting and the military combat setting. Hemostatic resuscitation with increased emphasis on blood transfusion while limiting use of crystalloids has become routine in trauma care. However, the prehospital setting-especially in combat-presents unique challenges with regard to storage, transport, and administration. We sought to evaluate available technology on the market for storage and administration technology that is relevant to the prehospital setting. STUDY DESIGN AND METHODS: We conducted a market review of available technology through subject-matter expert inquiry, reviews of published literature, reviews of Federal Drug Administration databases, internal military publications, and searches of Google. RESULTS: We reviewed and described a total of 103 blood transporters, 22 infusers, and 6 warmers. CONCLUSIONS: The risk of on-scene fatality in trauma patients and recent developments in trauma care demonstrate the need for prehospital transfusion. These transfusions have been logistically prohibited in many operations. We have reviewed the current commercially available equipment and recommended pursuit of equipment that improves accessibility to field transfusion. Current technology has limited applicability for the prehospital setting and is further limited for the military setting.

A Pilot Study to Assess Urban, Fire-Based Paramedic Accuracy in Identification of Anatomical Landmarks Necessary for Cricothyrotomy and Needle Chest Decompression Using Live Patient Models.

BACKGROUND: Cricothyrotomy and chest needle decompression (NDC) have a high failure and complication rate. This article sought to determine whether paramedics can correctly identify the anatomical landmarks for cricothyrotomy and chest NDC. METHODS: A prospective study using human models was performed. Paramedics were partnered and requested to identify the location for cricothyrotomy and chest NDC (both mid-clavicular and anterior axillary sites) on each other. A board-certified or board-eligible emergency medicine physician timed the process and confirmed location accuracy. All data were collected de-identified. Descriptive analysis was performed on continuous data; chi-square was used for categorical data. RESULTS: A total of 69 participants were recruited, with one excluded for incomplete data. The paramedics had a range of six to 38 (median 14) years of experience. There were 28 medical training officers (MTOs) and 41 field paramedics. Cricothyroidotomy location was correctly identified in 56 of 68 participants with a time to identification range of 2.0 to 38.2 (median 8.6) seconds. Chest NDC (mid-clavicular) location was correctly identified in 54 of 68 participants with a time to identification range of 3.4 to 25.0 (median 9.5) seconds. Chest NDC (anterior axillary) location was correctly identified in 43 of 68 participants with a time to identification range of 1.9 to 37.9 (median 9.6) seconds. Chi-square (2-tail) showed no difference between MTO and field paramedic in cricothyroidotomy site (P = .62), mid-clavicular chest NDC site (P = .21), or anterior axillary chest NDC site (P = .11). There was no difference in time to identification for any procedure between MTO and field paramedic. CONCLUSION: Both MTOs and field paramedics were quick in identifying correct placement of cricothyroidotomy and chest NDC location sites. While time to identification was clinically acceptable, there was also a significant proportion that did not identify the correct landmarks.

Operationalizing the Deployment of Low-Titer O-Positive Whole Blood Within a Regional Trauma System.

INTRODUCTION: The implementation of a low-titer O+ whole blood (LTOWB) resuscitation algorithm, particularly in the prehospital environment, has several inherent challenges, including cost, limited and inconsistent supply, and the logistics of cold-chain management. The Southwest Texas Regional Advisory Council has implemented the nation's first multidisciplinary, multi-institutional regional LTOWB program. This research effort was to illustrate the successful deployment of LTOWB within a regional trauma system. MATERIALS AND METHODS: A deliberate systems approach to the deployment of LTOWB was used. Tenets of this program included the active management of blood donor sources and blood supply levels to minimize wastage as a result of expiration, maximize product utilization, the use of prehospital transfusion triggers, and efforts to decrease program costs prehospital agencies. A novel LTOWB rotation system was established using the concept of a "rotation site" and "rotation center." Standardized transfusion criteria, a regional approved equipment list, a regional Prehospital Blood Product Transfusion Record, and a robust multilevel communication plan serves as the framework for the program. The San Antonio Whole Blood Consortium was developed to create a consensus driven forum to manage and guide the program. RESULTS: From January 2018 to October 2019, LTOWB has been placed at 18 helicopter emergency medical services (HEMS) bases, 12 ground emergency medical service (EMS) agencies, 1 level I trauma center, and 1 level IV trauma center. A total of 450 patients have received a prehospital LTOWB transfusion. Program wide, the wastage rate of LTOWB due to expiration is between 1% and 2%. No complications related to prehospital LTOWB administration have been identified. DISCUSSION: This work demonstrates a novel model for the development of a trauma system LTOWB program. The program's implementation augments remote damage control resuscitation strategies and requires the integration and collaboration of a multidisciplinary stakeholder team to optimize efficiency, performance, and safety of the program.

Paramedic utilization of Vision, Aphasia, Neglect (VAN) stroke severity scale in the prehospital setting predicts emergent large vessel occlusion stroke.

BACKGROUND: Numerous stroke severity scales have been published, but few have been studied with emergency medical services (EMS) in the prehospital setting. We studied the Vision, Aphasia, Neglect (VAN) stroke assessment scale in the prehospital setting for its simplicity to both teach and perform. This prospective prehospital cohort study was designed to validate the use and efficacy of VAN within our stroke systems of care, which includes multiple comprehensive stroke centers (CSCs) and EMS agencies. METHODS: The performances of VAN and the National Institutes of Health Stroke Scale (NIHSS) ≥6 for the presence of both emergent large vessel occlusion (ELVO) alone and ELVO or any intracranial hemorrhage (ICH) combined were reported with positive predictive value, sensitivity, negative predictive value, specificity, and overall accuracy. For subjects with intraparenchymal hemorrhage, volume was calculated based on the ABC/2 formula and the presence of intraventricular hemorrhage was recorded. RESULTS: Both VAN and NIHSS ≥6 were significantly associated with ELVO alone and with ELVO or any ICH combined using χ2 analysis. Overall, hospital NIHSS ≥6 performed better than prehospital VAN based on statistical measures. Of the 34 cases of intraparenchymal hemorrhage, mean±SD hemorrhage volumes were 2.5±4.0 mL for the five VAN-negative cases and 17.5±14.2 mL for the 29 VAN-positive cases. CONCLUSIONS: Our VAN study adds to the published evidence that prehospital EMS scales can be effectively taught and implemented in stroke systems with multiple EMS agencies and CSCs. In addition to ELVO, prehospital scales such as VAN may also serve as an effective ICH bypass tool.

Prehospital Battlefield Casualty Intervention Decision Cognitive Study.

INTRODUCTION: Airway compromise is the third most common cause of preventable battlefield death. Surgical cricothyroidotomy (SC) is recommended by Tactical Combat Casualty Care (TCCC) guidelines when basic airway maneuvers fail. This is a descriptive analysis of the decision-making process of prehospital emergency providers to perform certain airway interventions. METHODS: We conducted a scenario-based survey using two sequential video clips of an explosive injury event. The answers were used to conduct descriptive analyses and multivariable logistic regression models to estimate the association between the choice of intervention and training factors. RESULTS: There were 254 respondents in the survey, 176 (69%) of them were civilians and 78 (31%) were military personnel. Military providers were more likely to complete TCCC certification (odds ratio [OR]: 13.1; confidence interval [CI]: 6.4-26.6; P-value < 0.001). The SC was the most frequently chosen intervention after each clip (29.92% and 22.10%, respectively). TCCC-certified providers were more likely to choose SC after viewing the two clips (OR: 1.9; CI: 1.2-3.2; P-value: 0.009), even after controlling for relevant factors (OR: 2.3; CI: 1.1-4.8; P-value: 0.033). CONCLUSIONS: Military providers had a greater propensity to be certified in TCCC, which was found to increase their likelihood to choose the SC in early prehospital emergency airway management.

Dispatcher Identification of Out-of-Hospital Cardiac Arrest and Neurologically Intact Survival: A Retrospective Cohort Study.

INTRODUCTION: To date, there are no published data on the association of patient-centered outcomes and accurate public-safety answering point (PSAP) dispatch in an American population. The goal of this study is to determine if PSAP dispatcher recognition of out-of-hospital cardiac arrest (OHCA) is associated with neurologically intact survival to hospital discharge. METHODS: This retrospective cohort study is an analysis of prospectively collected Quality Assurance/Quality Improvement (QA/QI) data from the San Antonio Fire Department (SAFD; San Antonio, Texas USA) OHCA registry from January 2013 through December 2015. Exclusion criteria were: Emergency Medical Services (EMS)-witnessed arrest, traumatic arrest, age <18 years old, no dispatch type recorded, and missing outcome data. The primary exposure was dispatcher recognition of cardiac arrest. The primary outcome was neurologically intact survival (defined as Cerebral Performance Category [CPC] 1 or 2) to hospital discharge. The secondary outcomes were: bystander cardiopulmonary resuscitation (CPR), automated external defibrillator (AED) use, and prehospital return of spontaneous return of circulation (ROSC). RESULTS: Of 3,469 consecutive OHCA cases, 2,569 cases were included in this analysis. The PSAP dispatched 1,964/2,569 (76.4%) of confirmed OHCA cases correctly. The PSAP dispatched 605/2,569 (23.6%) of confirmed OHCA cases as another chief complaint. Neurologically intact survival to hospital discharge occurred in 99/1,964 (5.0%) of the recognized cardiac arrest group and 28/605 (4.6%) of the unrecognized cardiac arrest group (OR = 1.09; 95% CI, 0.71-1.70). Bystander CPR occurred in 975/1,964 (49.6%) of the recognized cardiac arrest group versus 138/605 (22.8%) of the unrecognized cardiac arrest group (OR = 3.34; 95% CI, 2.70-4.11). CONCLUSION: This study found no association between PSAP dispatcher identification of OHCA and neurologically intact survival to hospital discharge. Dispatcher identification of OHCA remains an important, but not singularly decisive link in the OHCA chain of survival.

Association of patient age with first pass success in out-of-hospital advanced airway management.

BACKGROUND: First pass advanced airway insertion success is associated with fewer adverse events. We sought to compare out-of-hospital endotracheal intubation (ETI) and supraglottic airway (SGA) first-pass success (FPS) rates between adults and children in a national cohort of EMS agencies. METHODS: We analyzed data from 2017 using a national cohort of 731 EMS agencies. Using multivariable logistic regression, we compared the odds of ETI and SGA FPS between adult (age >14 years) and pediatric (age ≤14 years) patients, adjusting for gender, ethnicity, indication, and drug facilitation. We performed a sensitivity analysis of all patients using age as a continuous variable for both ETI and SGA FPS. Finally, we calculated the odds of FPS using all possible age break points between 10 and 18 years old. RESULTS: A total of 29,368 patients (28,846 adults and 522 children) received ETI (22,519) or SGA (6849). ETI FPS was higher in adults than children; 72.7% vs, 58.5%, (OR 1.80, 95% CI 1.49-2.17). SGA FPS was similar between adults and children; 89.8% vs 84.6%, (OR 1.63, CI 0.70-3.31). When analyzed as a continuous variable, ETI FPS remained associated with age in years: OR 1.007 (CI 1.006-1.009) and SGA FPS showed no significant association with age: OR 0.999 (0.995-1.004). The OR for ETI FPS were higher in adults than pediatrics at all potential age break points between 10 and 18 years old. The OR for SGA FPS was significantly more likely in adults than pediatrics using 16 as a break point but not significantly different between adults and pediatrics using any other age break point. CONCLUSION: In this national cohort of out-of-hospital patients, ETI FPS was higher for adults than children. SGA FPS did not significantly vary with age. SGA FPS was higher than ETI FPS at all ages.

External Soft-Tissue Hemostatic Clamp Compared to a Compression Tourniquet as Primary Hemorrhage Control Device in Pilot Flow Model Study.

INTRODUCTION: Acute blood loss represents a leading cause of death in both civilian and battlefield trauma, despite the prioritization of massive hemorrhage control by well-adopted trauma guidelines. Current Tactical Combat Casualty Care (TCCC) and Tactical Emergency Casualty Care (TECC) guidelines recommend the application of a tourniquet to treat life-threatening extremity hemorrhages. While extremely effective at controlling blood loss, the proper application of a tourniquet is associated with severe pain and could lead to transient loss of limb function impeding the ability to self-extricate or effectively employ weapons systems. As a potential alternative, Innovative Trauma Care (San Antonio, Texas USA) has developed an external soft-tissue hemostatic clamp that could potentially provide effective hemorrhage control without the aforementioned complications and loss of limb function. Thus, this study sought to investigate the effectiveness of blood loss control by an external soft-tissue hemostatic clamp versus a compression tourniquet. HYPOTHESIS: The external soft-tissue hemostatic clamp would be non-inferior at controlling intravascular fluid loss after damage to the femoral and popliteal arteries in a normotensive, coagulopathic, cadaveric lower-extremity flow model using an inert blood analogue, as compared to a compression tourniquet. METHODS: Using a fresh cadaveric model with simulated vascular flow, this study sought to compare the effectiveness of the external soft-tissue hemostatic clamp versus the compression tourniquet to control fluid loss in simulated trauma resulting in femoral and posterior tibial artery lacerations using a coagulopathic, normotensive, cadaveric-extremity flow model. A sample of 16 fresh, un-embalmed, human cadaver lower extremities was used in this randomized, balanced two-treatment, two-period, two-sequence, crossover design. Statistical significance of the treatment comparisons was assessed with paired t-tests. Results were expressed as the mean and standard deviation (SD). RESULTS: Mean intravascular fluid loss was increased from simulated arterial wounds with the external soft-tissue hemostatic clamp as compared to the compression tourniquet at the lower leg (119.8mL versus 15.9mL; P <.001) and in the thigh (103.1mL versus 5.2mL; P <.001). CONCLUSION: In this hemorrhagic, coagulopathic, cadaveric-extremity experimental flow model, the use of the external soft-tissue hemostatic clamp as a hasty hemostatic adjunct was associated with statistically significant greater fluid loss than with the use of the compression tourniquet.Paquette R, Bierle R, Wampler D, Allen P, Cooley C, Ramos R, Michalek J, Gerhardt RT. External soft-tissue hemostatic clamp compared to a compression tourniquet as primary hemorrhage control device in pilot flow model study. Prehosp Disaster Med. 2019;34(2):175-181.

Prehospital Double Sequential Defibrillation: A Matched Case-Control Study.

OBJECTIVES: The goal of our study was to determine whether prehospital double sequential defibrillation (DSD) is associated with improved survival to hospital admission in the setting of refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT). METHODS: This project is a matched case-control study derived from prospectively collected quality assurance/quality improvement data obtained from the San Antonio Fire Department out-of-hospital cardiac arrest (OHCA) database between January 2013 and December 2015. The cases were defined as OHCA patients with refractory VF/pVT who survived to hospital admission. The control group was defined as OHCA patients with refractory VF/pVT who did not survive to hospital admission. The primary variable in our study was prehospital DSD. The primary outcome of our study was survival to hospital admission. RESULTS: Of 3,469 consecutive OHCA patients during the study period, 205 OHCA patients met the inclusion criterion of refractory VF/pVT. Using a predefined algorithm, two blinded researchers identified 64 unique cases and matched them with 64 unique controls. Survival to hospital admission occurred in 48.0% of DSD patients and 50.5% of the conventional therapy patients (p > 0.99; odds ratio = 0.91, 95% confidence interval = 0.40-2.1). CONCLUSION: Our matched case-control study on the prehospital use of DSD for refractory VF/pVT found no evidence of associated improvement in survival to hospital admission. Our current protocol of considering prehospital DSD after the third conventional defibrillation in OHCA is ineffective.

Stop the Bleed: The Effect of Hemorrhage Control Education on Laypersons' Willingness to Respond During a Traumatic Medical Emergency.

BACKGROUND: The "Stop the Bleed" campaign advocates for non-medical personnel to be trained in basic hemorrhage control. However, it is not clear what type of education or the duration of instruction needed to meet that requirement. The objective of this study was to determine the impact of a brief hemorrhage control educational curriculum on the willingness of laypersons to respond during a traumatic emergency. METHODS: This "Stop the Bleed" education initiative was conducted by the University of Texas Health San Antonio Office of the Medical Director (San Antonio, Texas USA) between September 2016 and March 2017. Individuals with formal medical certification were excluded from this analysis. Trainers used a pre-event questionnaire to assess participants knowledge and attitudes about tourniquets and responding to traumatic emergencies. Each training course included an individual evaluation of tourniquet placement, 20 minutes of didactic instruction on hemorrhage control techniques, and hands-on instruction with tourniquet application on both adult and child mannequins. The primary outcome in this study was the willingness to use a tourniquet in response to a traumatic medical emergency. RESULTS: Of 236 participants, 218 met the eligibility criteria. When initially asked if they would use a tourniquet in real life, 64.2% (140/218) responded "Yes." Following training, 95.6% (194/203) of participants responded that they would use a tourniquet in real life. When participants were asked about their comfort level with using a tourniquet in real life, there was a statistically significant improvement between their initial response and their response post training (2.5 versus 4.0, based on 5-point Likert scale; P<.001). CONCLUSION: In this hemorrhage control education study, it was found that a short educational intervention can improve laypersons' self-efficacy and reported willingness to use a tourniquet in an emergency. Identified barriers to act should be addressed when designing future hemorrhage control public health education campaigns. Community education should continue to be a priority of the "Stop the Bleed" campaign. Ross EM , Redman TT , Mapp JG , Brown DJ , Tanaka K , Cooley CW , Kharod CU , Wampler DA . Stop the bleed: the effect of hemorrhage control education on laypersons' willingness to respond during a traumatic medical emergency. Prehosp Disaster Med. 2018;33(2):127-132.

No Benefit in Neurologic Outcomes of Survivors of Out-of-Hospital Cardiac Arrest with Mechanical Compression Device.

INTRODUCTION: Out-of-hospital cardiac arrest (OHCA) is a major cause of death and morbidity in the United States. Quality cardiopulmonary resuscitation (CPR) has proven to be a key factor in improving survival. The aim of our study was to investigate the outcomes of OHCA when mechanical CPR (LUCAS 2 Chest Compression System™) was utilized compared to conventional CPR. Although controlled trials have not demonstrated a survival benefit to the routine use of mechanical CPR devices, there continues to be an interest for their use in OHCA. METHODS: We conducted a retrospective observational study of OHCA comparing the outcomes of mechanical and manual chest compressions in a fire department based EMS system serving a population of 1.4 million residents. Mechanical CPR devices were geographically distributed on 11 of 33 paramedic ambulances. Data were collected over a 36-month period and outcomes were dichotomized based on utilization of mechanical CPR. The primary outcome measure was survival to hospital discharge with a cerebral performance category (CPC) score of 1 or 2. RESULTS: This series had 3,469 OHCA reports, of which 2,999 had outcome data and met the inclusion criteria. Of these 2,236 received only manual CPR and 763 utilized a mechanical CPR device during the resuscitation. Return of spontaneous circulation (ROSC) was attained in 44% (334/763) of the mechanical CPR resuscitations and in 46% (1,020/2,236) of the standard manual CPR resuscitations (p = 0.32). Survival to hospital discharge was observed in 7% (52/763) of the mechanical CPR resuscitations and 9% (191/2,236) of the manual CPR group (p = 0.13). Discharge with a CPC score of 1 or 2 was observed in 4% (29/763) of the mechanical CPR resuscitation group and 6% (129/2,236) of the manual CPR group (p = 0.036). CONCLUSIONS: In our study, use of the mechanical CPR device was associated with a poor neurologic outcome at hospital discharge. However, this difference was no longer evident after logistic regression adjusting for confounding variables. Resuscitation management following institution of mechanical CPR, specifically medication and airway management, may account for the poor outcome reported. Further investigation of resuscitation management when a mechanical CPR device is utilized is necessary to optimize survival benefit.

Compensatory Reserve Index: Performance of A Novel Monitoring Technology to Identify the Bleeding Trauma Patient.

INTRODUCTION: Hemorrhage is one of the most substantial causes of death after traumatic injury. Standard measures, including systolic blood pressure (SBP), are poor surrogate indicators of physiologic compromise until compensatory mechanisms have been overwhelmed. Compensatory Reserve Index (CRI) is a novel monitoring technology with the ability to assess physiologic reserve. We hypothesized CRI would be a better predictor of physiologic compromise secondary to hemorrhage than traditional vital signs. METHODS: A prospective observational study of 89 subjects meeting trauma center activation criteria at a single level I trauma center was conducted from October 2015 to February 2016. Data collected included demographics, SBP, heart rate, and requirement for hemorrhage-associated, life-saving intervention (LSI) (i.e., operation or angiography for hemorrhage, local or tourniquet control of external bleeding, and transfusion >2 units PRBC). Receiver-operator characteristic (ROC) curves were formulated and appropriate thresholds were calculated to compare relative value of the metrics for predictive modeling. RESULTS: For predicting hemorrhage-related LSI, CRI demonstrated a sensitivity of 83% and a negative predictive value (NPV) of 91% as compared with SBP with a sensitivity to detect hemorrhage of 26% (P < 0.05) and an NPV of 78%. ROC curves generated from admission CRI and SBP measures demonstrated values of 0.83 and 0.62, respectively. CRI identified significant hemorrhage requiring potentially life-saving therapy more reliably than SBP (P < 0.05). CONCLUSION: The CRI device demonstrated superior capacity over systolic blood pressure in predicting the need for posttraumatic hemorrhage intervention in the acute resuscitation phase after injury.

Does Experience Matter? Paramedic Cardiac Resuscitation Experience Effect on Out-of-Hospital Cardiac Arrest Outcomes.

OBJECTIVE: Outcomes of Out-of-Hospital Cardiac Arrest (OHCA) are influenced by many factors. We postulate that paramedics who have participated in a greater number of OHCA resuscitations will have improved patient outcomes when compared to paramedics who participated in fewer resuscitations. METHODS: We conducted a retrospective analysis of prospectively collected data abstracted from the cardiac arrest database of a large urban EMS system. All OHCA cases where resuscitation was attempted during the year 2014 were reviewed. Our outcome of interest was the rate of sustained Return of Spontaneous Circulation (ROSC), which is defined as ROSC for five continuous minutes or greater. The rate of sustained ROSC was calculated from cases when paramedics served in the role of the lead medic. These rates were then analyzed using the Chi-Square test. RESULTS: A total of 1,145 cases of OHCA met criteria for inclusion in this study, of which 343 paramedics participated in at least one cardiac arrest in 2014. The median number of resuscitations was 10 with a range from 1 to 26 resuscitations. The paramedics were dichotomized into two groups; those who participated in <10 OHCAs (120/343), labeled "less experienced," and those who participated in ≥10 OHCAs (223/343), labeled "more experienced." Paramedics in the less experienced group had a sustained ROSC rate of 22.2% for resuscitations in which they were the lead medic, while those in the more experienced group had a rate of 28.9% (p-value = 0.047), RR 1.30 (95% CI 1.001, 1.692). CONCLUSIONS: This study demonstrated that more experienced paramedics had a statistically significant increase in achieving sustained ROSC when they were functioning in a lead role compared to less experienced paramedics. We found no other clinically significant patient outcomes related to the provider's experience.

The Tourniquet Gap: A Pilot Study of the Intuitive Placement of Three Tourniquet Types by Laypersons.

BACKGROUND: The "Stop the Bleed" campaign in the United States advocates for nonmedical personnel to be trained in basic hemorrhage control and that "bleeding control kits" be available in high-risk areas. However, it is not clear which tourniquets are most effective in the hands of laypersons. OBJECTIVES: The objective of this pilot study was to determine which tourniquet type was the most intuitive for a layperson to apply correctly. METHODS: This project is a randomized study derived from a "Stop the Bleed" education initiative conducted between September 2016 and March 2017. Novice tourniquet users were randomized to apply one of three commercially available tourniquets (Combat Action Tourniquet [CAT; North American Rescue, LLC, Greer, SC], Ratcheting Medical Tourniquet [RMT; m2 Inc., Winooski, VT], or Stretch Wrap and Tuck Tourniquet [SWAT-T; TEMS Solutions, LLC, Salida, CO]) in a controlled setting. Individuals with formal medical certification, prior military service, or prior training with tourniquets were excluded. The primary outcome of this study was successful tourniquet placement. RESULTS: Of 236 possible participants, 198 met the eligibility criteria. Demographics were similar across groups. The rates of successful tourniquet application for the CAT, RMT, and SWAT-T were 16.9%, 23.4%, and 10.6%, respectively (p = 0.149). The most common causes of application failure were: inadequate tightness (74.1%), improper placement technique (44.4%), and incorrect positioning (16.7%). CONCLUSION: Our pilot study on the intuitive nature of applying commercially available tourniquets found unacceptably high rates of failure. Large-scale community education efforts and manufacturer improvements of tourniquet usability by the lay public must be made before the widespread dissemination of tourniquets will have a significant public health effect.